This component keeps track of the value for a given column in the database. If
you change the columns value and do not call update, the storage_value
will be different; once update is called the storage_value will be set
to the value of the accessor. Note that the fact that it uses the accessor is
an important distinction. If you are using DBIx::Class::FilterColumn or
DBIx::Class::InflateColumn it will get the non-storage or inflated values,
respectively.